As designs are increasingly attractive to consumers, designs for buttons are becoming more and more diversified. One of them is a button having a light emitting effect. The conventional light-emitting button includes a light guiding board and multiple LED lights with the LED lights evenly distributed along the edges of the light guiding board to achieve an evenly light emitting effect on both sides of the light guiding board. One problem with such design is that it requires multiple LED lights and is not energy efficient.